hormonal change

is it normal to have a sudden hormonal change while on the pill? i started my period early this month, only a week between this one and my last one, and its been really light but long (almost 2 weeks.) ive also recently broken out quite a bit more than usual and been feeling really fat and sluggish. ive gained a few pounds despite eating well. its worth noting that i went vegetarian over a month ago now. But i'd just like to know if anyone else on the pill has experienced this? is it normal? can i do anything to remedy it? thanks!